1. Technical Field
The present invention relates to a wooden building skeleton composed of wooden columns, beams, load-bearing walls and so on which resist a horizontal force, and, more particularly, to a wooden building skeleton including a column having an upper or lower end joined to a cross member, such as a beam, or the foundation in such a way that a bending moment can be transferred therebetween.
2. Related Art
Many of wooden buildings constituted of columns and cross members, such as beams, have load-bearing walls formed by providing braces between columns or load-bearing walls formed by securing facing materials between columns to form a framework structure which resists horizontal forces during an earthquake or the like. In such a structure, the columns on both sides of a load-bearing wall serve as shaft columns which do not transfer and receive a bending moment to and from a cross member, such as a beam, base or girt, and supports a beam or the like mainly by means of an axial force, and braces or facing materials constrain the shaft columns from tilting.
On the other hand, it is proposed to introduce a rigid-frame structure in which columns and cross members, such as beams, are joined in such a way that a bending moment can be transferred therebetween as a structure different from the framework structure also into wooden buildings as disclosed in Patent Literature 1, for example. A rigid-frame structure facilitates the creation of a residential space with few columns and the formation of a large opening in exterior walls. In such a rigid-frame structure, horizontal forces during an earthquake or the like are resisted by the bending rigidity of columns and the bending rigidity of cross members or the like joined to the columns in such a way that a bending moment can be transferred therebetween.
When a wooden building with a structural skeleton having a rigid-frame structure as described above is constructed, shaft columns are usually installed, in addition to the columns forming the rigid-frame structure, beneath the beams to form additional exterior walls or partition walls. Patent Literature 2 discloses the use of such exterior walls or partition walls as load-bearing walls which form a part of the structural skeleton. When exterior walls or partition wall can serve to resist horizontal forces during an earthquake or the like, a highly economical structure may be achieved because the number of columns having a rigid-frame structure can be reduced.    [Patent Literature 1] JPA-Publication No. 2004-92150    [Patent Literature 2] JPA-Publication No. 2006-118275
However, a column or beam having a rigid-frame structure and a load-bearing wall using a facing material are completely different in the mechanism involved in resisting a horizontal force and exhibits different deformational characteristics when subjected to a horizontal force. In particular, the amount of inter-story deflection, in other words, the horizontal relative displacement in the axial direction of a beam supported by a column between the beam and the foundation or a beam of the lower story, before a column or load-bearing wall loses its load bearing ability may be completely different. When there is such a difference in characteristics, when horizontal forces, such as forces generated by earthquake motion, are repeatedly applied, functional deterioration may occur in a part of the structural skeleton earlier than in the other parts. Then, the ability to absorb the energy of earthquake motion repeatedly applied may decrease.
The present invention has been made in view of the above circumstances, and it is, therefore, an object of the present invention to provide a wooden building skeleton which has excellent quake resistance because a column having a rigid-frame structure and joined to a cross member or foundation in such a way that a bending moment can be transferred therebetween and a load-bearing wall therein fully exhibit their load bearing ability and ability to absorb vibrational energy.